A VIM induction furnace is a type of induction heating furnace that is operated in a vacuum chamber. The vacuum chamber is designed to enclose the entire induction furnace. Non-limiting examples of VIM induction furnaces are disclosed in U.S. Pat. No. 6,623,598; U.S. Pat. No. 6,360,810; U.S. Pat. No. 5,372,355; U.S. Pat. No. 4,557,757; US 2007/0022841; US 2002/0056538; EP 1118684; and EP 1114872, all of which are all fully incorporated herein by reference. Similar to all other types of industrial equipment, the induction furnace must be periodically serviced. Such service can include relining or other types of repairs to the induction system. Depending on the type of VIM induction furnace and the operational conditions of the VIM induction furnace, such service can occur quite often. The induction furnace generally cannot be serviced while inside the vacuum chamber. As such, the induction furnace typically must be removed from the vacuum chamber for servicing and another induction furnace is generally inserted into the vacuum chamber while the induction furnace that was recently removed is serviced. As such, one induction furnace is typically removed from the vacuum chamber and repaired while another induction furnace is typically inserted into the vacuum chamber and used to heat materials. This type of setup ensures that there is always a working induction furnace in the vacuum chamber, thereby reducing lost production time.
Although the switching of induction furnaces reduces lost production time, there is still significant lost time during the switch out process. The “hot” induction furnace must generally be allowed to cool down before removal from the vacuum chamber. While in service, the induction furnace has cooling water circulating through the induction coils. The flow of cooling water must be maintained until the induction furnace cools sufficiently or damage to the induction coils may result. This cool-down time results in a loss in production time. Depending on the size of the induction furnace and the temperatures reached during a heating process, the cool-down time for the induction furnace can be many hours or a number of days.
In view of the current state of the art of VIM induction furnaces, there remains a need to quickly switch out induction furnaces so as to reduce production losses traditionally encountered when waiting for an induction furnace to sufficiently cool prior to beginning the induction furnace change out.